The present invention relates to a container which allows its contents to be cooled by an evaporation and adsorption method. The principle of a such a cooling method consists of evaporating a liquid, called refrigerant, under the action of a depression maintained by pumping the vapors of said liquid. The invention applies to the cooling of food products such as beverages, ice creams, but also to non-food products such as pharmaceuticals or cosmetics.
The invention applies quite particularly to the cooling of a beverage contained in a closed container of can or bottle type.
An aim of the present invention is therefore to allow the consumption of a beverage at an ideal temperature in any place and at any time.
The implementation of the method of cooling by evaporation and adsorption is known and has been the subject of numerous research programmes in the prior art. Numerous devices have been proposed, combining a heat exchanger containing a liquid to be evaporated with a reservoir containing an adsorbent, in particular for applications to self-cooling beverage containers.
Thus, U.S. Pat. No. 4,928,495, an illustration of which is given in FIG. 1, discloses a self-cooling container configuration 10 (presented as a can) comprising a heat exchanger 16 of flattened rectangular shape immersed in a beverage to be cooled and connected to an adsorption device 22. This patent discloses an outline scheme without specifying the means of producing such a device taking account of the economic constraints associated with an application to disposable containers.
Moreover, International Patent Application WO 01/11297, an illustration of which is given in FIG. 2a, also discloses a self-cooling beverage container and specifies the geometry of the heat exchanger as well as the manufacturing and assembly process of such a device which is compatible with the industrial constraints of high output volumes.
The beverage container described in this International Application is constituted by a closed first can 10 containing the consumer beverage and a heat exchanger 20 and a closed second can 30 containing desiccants 24. The two cans are assembled by a ring 29. Communication means 40 between said two cans must be actuated by a porous spike 44 to allow implementation of the cooling method by evaporation adsorption of the vapors of a refrigerant contained in the exchanger. These communication means, a detailed illustration of which is given in FIG. 2b, comprise a seal 66 comprising two membranes 70 and 71 arranged opposite each other in the walls of the first and second cans of the container respectively. The porous spike 44 makes it possible to tear the seal 66 so as to connect the desiccants reservoir 30 to the heat exchanger 20, thus triggering the evaporation reaction by adsorption and cooling the beverage.
This document also discloses the manufacturing process of such a self-cooling beverage container and in particular the assembly stages of the different elements constituting the container. The assembly stage of the first can 10, containing the beverage and the heat exchanger 20, with the can 30 containing the desiccants is particularly delicate as it is essential to maintain a high vacuum in the desiccants reservoir 30 and at the seal 66 so that the adsorption reaction can be actuated during tearing of the membranes 70 and 71. To this end, Application WO01/11297 proposes to place a drop of oil 73 between the two membranes 70 and 71 in order to guarantee a good tightness of the vacuum during assembly of the two cans.
However, the self-cooling beverage container as well as the process described in this Application WO01/11297 have certain drawbacks. In particular, the system of connecting the desiccants reservoir 30 to the heat exchanger 20 is not optimized. In fact, the two membranes 70 and 71 each have a relatively substantial thickness which is essential in resisting the external atmospheric pressure before assembly of the container. Moreover, these two membranes 70 and 71 constitute a double thickness which requires a major rupture force. To this end, the Patent Application specifies that the porous spike element 44 is actuated using a screw. Moreover, the production of such a seal 66 complicates assembly of the container, in particular with the requirement to keep the interstice between the two membranes 70 and 71 under air vacuum, when one of them turns relative to the other.